Air diffuser



Nov. 12, 1935. H. E. OSKAMP 7 2,021,086

' AiR DIFFUSER Original Filed Jan. 25, 1935 INVENTOR.

' 'HO ARDE. OSKAMP. Z W I ATTORNEY.

Patented Nov. 12, 1935 UNITED STATES PATIENT OFFICE AIR DIFFUSER Howard E. Oskamp, Wheaten, lll.

Refiled for abandoned application, Serial No. 493,085, November 3, 1930, and a division of application January 23, 1933, Serial No. 653,075. This application March 20, 1934, Serial No.

8 Claims.

My invention relates in general to air distribution, and in particular to a device for attachment to a fan to diffuse air driven from the fan, uniformly over the space in which said fan is situated. The present application is a division of my application, Serial No. 653,075, filed January 23, 1933, and a refiling of the subject matter of abandoned application, Serial No. 493,085, filed November 3, 1930.

The air blast from the ordinary electric fan is concentrated within a limited area, usually to the discomfort of a person sitting or standing immediately in front of the same.

It is an object of my invention to change the strong, direct current of air from a fan into a diffused, uniform distribution of air immediately in front of the fan as well as at any distant point therefrom.

A further object is to provide an attachment for a fan which will difiuse the air blast from said fan and uniformly distribute said air, without at the same time building up a resistance to the movement of the air blast so as to form a back pressure on the fan blades and heat the fan motor to reduce the operating efiiciency of the same. v

A still further object of my invention is to provide a maximum mixing of moving air from an electric fan throughout the space into which the fan blows, and

It is also an object to provide a device for accomplishing the above result, which is simple, sturdy, and may be manufactured at a relatively low cost.

Other objects and advantages of my invention will be apparent from a consideration of the specification taken with the drawing, in which:

Fig. l is a front elevation of my air diffuser.

Fig. 2 is a sectional view of the diffuser along the line 2-4 of Fig. 1, mounted in front of an electric fan; and

Fig. 3 is a front elevation of a modified form of the invention.

Fig. 4 shows a method of enlarging openingsf In practicing my invention I provide a flat slotted plate for attachment to, or mounting in front of, an electric fan, with said plate having a plurality of defiectorsextending inwardly from the outer surface thereof. The deflectors are stamped from the plate at an angle and supporting ribs for the deflectors cut out so that the horizontal plane of the top of one deflector is slightly removed from a like plane of the bottom of the deflector immediately above the first to provide a horizontal as well as an inclined passage of substantial opening between adjacent deflectors to provide air diffusion forwardly and outwardly from the front of the plate when mounted in front of a fan.

A direct air blast from a fan is ordinarily ob- 5 jectionable because it is driven from the fan in a concentrated area. In order to prevent this, it is desirable to spread out the blast so as to move a larger body of air with the same rotation of the fan. I am familiar with devices of the prior art which have attempted to accomplish this result, but in those devices where a larger body of air is moved, it is not moved in a direction to obtain a gentle diffused action, most pleasant to the occupants of the room..

Furthermore, in those devices with which I am familiar, where a movement of air is obtained approaching the desired result, the device is so constructed as to resist the movement of the air from the fan, and build up a back pressure which will put a tremendous load on the fan motor. This condition reduces the operat ing efiiciency of the motor and causes heating such as to stop its operation.

The air diffuser 36 as illustrated in Fig. 1 is circular in form and consists of a series of deflectors 31 which are inclined inwardly preferably at an angle of approximately 45 to the axis of rotation of the fan 26. The deflectors 31 are spaced apart radially to provide passages or slots 38 between adjacent deflectors with the latter forming inclined walls for the slots.

The deflectors are preferably arranged in successive rows concentrically disposed around a central axis leaving supporting radial ribs or arms 39 spaced at intervals around the entire diffuser and extending radially from the center portion 4!. The deflectors 31 themselves are preferably stamped out of the metal of the frame and supported from connecting ribs 40. In 40 stamping out the diffuser from a single piece of metal, the deflectors are formed inwardly as heretofore described, by shearing them out of the metal so that the free edge of each deflector blade 31 is spaced from the adjacent edge of the opening 40 to provide an opening in a horizontal plane indicated by the lines A-B to allow a suflicient amount of air to pass through to pre-' vent back pressure on the fan. This construction is illustrated by dotted lines A and B in Fig. 2, and provides a horizontal passage for the air blast to prevent the objectionable back pressure heretofore discussed, and temper the deflection from the blades 31. To provide this desired opening without bending the blades 31 back too far I preferably cut out an additional portion of the metal adjacent each blade as indicated by 38a in Fig. 4.

Slotted openings 44 are also provided adjacent the outer edge of the plate to permit air to how out around the peripheral edge of the plate.

Although the air diffuser is not illustrated as mounted on the ordinary wire guard for an electric fan, it is of course understood that this may readily be done. An integral rearwardlly extending rim "serves as an anchoring flange for mounting the diffuser in front of, or on a fan.

This rim 42 also cooperating with the center portion 4| supports the arms 39 to provide a sturdy, rigid but simple integral construction in the diffuser. The rim 42 also assists in the efiective operation of a fan and the difiuser mounted on said fan in that it serves as a baffle to prevent the radial flow of air from the fan, and further, serves as a dividing wall between the air flowing out from the fan and the air being sucked into the fan.

In the use of the diffuser I have found that the highest efficiency both as to the diffusion of the air blast, and the operation of the fan, is obtained by positioning the difiuser on the fan 26 so that the blades rotate close to the difiuser, preferably from about one-half to three-quarters of an inch removed from the inner edges of the deflectors 31. With the individual deflectors extending inwardly from the flat outer surface of the plate and over the entire body of the diffuser substantially the entire air blast is acted upon almost immediately upon leaving the fan blades. This assists in reducing the air resistance to a negligible amount to in turn reduce the load on the fan motor.

With the use of the air diffuser 36, therefore, the direct longitudinally moving air column from the fan 26 is spread out radially into a substantially conical form, causing the moving air to mix and intermingle with the surrounding relatively still air in a gentle but effective uniform circulation throughout the entire room.

A modification of the diffuser is illustrated in Fig. 3 which is substantially square in shape. This difiuser 16 comprises four triangular deflector sections made up of individual deflectors 11 formed at an angle of 45 with the axis of rotation of the fan, similar to deflectors 31 and having passages 18 between planes of adjacent deflectors. Arms 19 separate thedeflector sections and serve as supports for the deflectors 11, while the arms in turn are supported between the rim 8| and the center portion 82. The air is projected from the diffuser 16 substantially in the form of an inverted pyramid to circulate the air uniformly over the room in which a fan and the diffuser are situated. It is also understood that other geometrical forms may be used for the diffuser, with each construction employing the same principles heretofore described.

Although I have described my invention in its preferred embodiments, it is understood that I do not limit myself thereby, but limit the invention only by the scope of the appended claims.

I claim:

1. A deflector adapted to be mounted in front of a rotatable fan, including a one-piece sheet metal plate having a plurality of elongated inwardly projecting deflector blades each sheared along three of its edges out of the face of the plate anddisposed in successive concentric rows about a central axis, said blades being bent toward the fan at an angle from the unsheared connected edge, and a supplemental cut-out portion adjacent the free edge joining with thecutout portion from the blade to provide an enlarged opening throughout the length of the free edge and corresponding thereto to permit a free 5 flow of air from the fan.

2. An air diffuser for-mounting in front of a fan blade comprising a circular plate having a flat outside face, an integral relatively narrow circumferential rim at the edge of the plate, a 10 plurality of arms extending outwardly from the center of the diffuser to the rim dividing said plate into a plurality of equi-area sectors, with each of said sectors including a plurality of radially spaced deflectors cut out from said plate 15 extending inwardly toward the axis of the fan, and an opening concentric with each deflector joining said deflector cut-out portion to provide an enlarged horizontal passage between adjacent -deflectors with said deflectors and passages 20 adapted to cause the air to diffuse forwardly and outwardly in a substantially conical form from the plate.

3. An air diffuser for mounting in front of a fan to direct air therefrom, said diifuser comprising a metal plate having a flat outside surface with a plurality of deflector sections extending over said plate, each section comprising a plurality of individual deflectors equally spaced apart over their length and extending inwardly 30 and toward the axis of the fan from a supporting strip in the flat outside surface, with each of said supporting strips integral with supporting arms extending in the outside surface of the plate outwardly from the center of said plate.

4. An air diffuser for mounting in front of a fan to direct air therefrom, said diffuser comprising a flat annular plate, having a plurality of deflector segments over the flat face of said plate positioned in pairs with the two segments in each pair extending outwardly in opposite. directions from the center of the diffuser, and each segment comprising a plurality of deflector blades extending inwardly toward the axis of the fan from the face of the plate. 45

5. An air diifuser for mounting in front of a fan to direct air therefrom, comprising a flat disc plate, a plurality of deflectors arranged in concentric circles over said plate, spaced apart radially and extending inwardly from the face 50 and toward the axis of the fan to provide a plurality of slotted spaces in the plate, said plate having a corresponding opening adjoining each of said slotted spaces forming an enlarged space between the plane of the top of one deflector 55 extending at from the face, and a corresponding plane of the bottom of the radially adjoining deflector, a plurality of supporting arms extending radially from a central portion of the plate at intervals around the plate to rigidly support 60 the deflectors, with each of saiddeflectors inclined inwardly toward the fan at such an angle with the axis of the fan as to direct the air from the fan substantially forwardly and conically from the diffuser.

6. .An air diffuser for mounting in front of a fan to direct air therefrom, comprising a flat disc plate, a plurality of deflectors arranged in concentric circles over said plate, spaced apart radially and extending inwardly from the face 7 and toward the axis of the fan to provide a plurality of slotted spaces in the plate, a pinrality of supporting arms extending radially from a central portion of the plate at equally spaced intervals around the plate to rigidly support the 75 deflectors, with each of said deflectors inclined inwardly from the face of said plate toward the fan at approximately 45 with a line extending perpendicularly from the center of the plate toward the fan, and adapted to cause the air from the fan to flow substantially forwardly and conically from the entire face of the difiuser.

'7. An air diffuser for mounting in front of a motor driven fan having a flat plate surface and air directing means over the entire plate, all inclined inwardly toward the axis of the fan and positioned for acting upon an air blast immediately in front of the fan blade to direct the entire blast substantially forwardly and conically from the entire front of the plate in such a manner that the blast is concentrated upon one sitting directly in front of the fan in a comfortable way.

8. An air diffuser for mounting in front of a fan to direct air therefrom, said difluser comprising a one-piece member having a flat outside surface with a plurality of deflector segments disposed over said surface, with one segment comprising a plurality of deflector blades extending from the face of the diffuser inwardly and upwardly, and with deflector segments adjacent thereto on each side, each having deflector blades extending from the face of the diifuser inwardly and sidewardly, and correspondingly positioned but oppositely positioned deflector segments on the remaining portion of said diffuser adapted to cause the air from the fan to flow substantially forwardly and conically from the front of the 15 difiuser.

HOWARD E. OSKAMP. 

